Round balers are used in order to produce bales from stalk-like harvested crops and have a baling chamber and compression elements surrounding the latter. The compression elements are usually configured as rolls or as endless traction elements in the form of chains having transverse elements or belts secured thereto. Such belts are used in particular in round balers having an variable bale diameter and rest on rolls, some of which are supported on the frame of the round baler and others of which can move with respect to the frame, in order to adapt the baling chamber to the gradually growing bale and to enable ejection of a finished bale.
The rolls, some of which are driven and others of which are freely running, extend transversely to the forward direction and the axis of the bale. Usually, a number of narrower compression belts are distributed over the width of the baling chamber or a single, wide compression belt is used (see e.g. U.S. Pat. No. 5,941,168 A1, which is considered to define the generic type). Since irregular distribution of harvested crop over the width of the baling chamber or displacement of the harvested crop to one side when work is carried out on a slope can lead to lateral displacement of the compression belt, and thus can result in undesired rubbing of the compression belt against the side wall of the round baler, guides for the compression belts have been proposed, these guides consist of rigid elements on which the compression belt rests laterally (see U.S. Pat. No. 5,261,323 A1). It has also been proposed to attach radially protruding rings on one of the rolls, so that the individual compression belts run through in each case between two rings (see U.S. Pat. No. 3,992,987 A1).
DE 528 450 C shows a belt conveyor which forms a reversing loop and the belt of which is guided in the lateral direction by freely rotatable discs which are located in the belt plane and butt against the edge of the belt. The subsequently published European Patent Application 10164609.9 describes a baler having a rear door which can be pivoted open and to which there are secured opposing guide rolls which enclose between one another a compression belt that extends over the width of the baling chamber.